Issue2349-instance-hidden.agda:12,16-20
x != c {_} ⦃ _ ⦄ {a} of type D {ℓ} ⦃ A ⦄
when checking that the expression refl has type
_≡_ {ℓ} {D {ℓ} ⦃ A ⦄} x (c {_} ⦃ _ ⦄ {a})
